#include<bits/stdc++.h>

using namespace std;

int main() {
	int a[] = {1, 6, 2, 5, 1, 2, 3,};
	int n = sizeof(a) / sizeof(a[0]);
	int b[10] = {0};
	for(int i = 0; i < n; i++) {
		b[a[i]]++;
	}
//	copy(b,b+10,ostream_iterator<int>(cout," "));
	for(int i=0;i<10;i++){
		if(b[i])cout<<i<<" ";
	} 
	return 0;
}
